Acute lymphoblastic leukaemia (ALL) is the most common form of childhood cancers. Cure rates are improving, but the intensity of treatment is limited by toxicity. 2-5% of patients die of treatment related complications, mostly related to therapy-induced toxicity and immune suppression. The aim of the present study is to evaluate the ability a colostrum containing diet to limit gastrointestinal toxicity including chemotherapy induced inflammation. The study is based on patients treated according to the current NOPHO protocol.